Forests and Shallow Seas

Carboniferous 286-360 million years ago

On display from the Carboniferous Period are fossils from the coral reefs and plant fossils from the earliest forests. The rotted carcasses of billions of these trees and ferns created the coal reserves that we mine today. At about 50cm diameter, Megarachne was first thought to be the largest known spider ever to have walked the Earth. Discovered in Argentina, the fossil was compressed between layers of Carboniferous rock. We now know the fossil is of that of a sea scorpion and not a spider. On display in this part of the Museum are a cast of the original fossil and, alongside it, a full-size model of the spider it was initially thought to be. This display was designed and produced by the Sedgwick Young Design Squad (SYDS).

Lepidodendron

Most of the trees which grew in the tropical forests of carboniferous times were quite different from those of modern forests. They included giant tree-sized clubmosses and horsetails, whose few modern representative are mostly less than a metre high. There were also many kinds of ferns, fern-like plants and some conifers, but none of the modern flowering plants. With warm wet climates, these ancient forests and swamps extended from North America through Europe and into Russia. Deep burial by geological processes produced coal from their organic debris.

Lepidodendron is an extinct Carboniferous clubmoss whose stem was covered with distinctive scaly scars, which originally carried leaves. Here, the pattern of scales has been moulded by sandy deposits.